Enlargement of the cerebral ventricles (ventriculomegaly) occurs in 1-2 per 1000 live births. Ventriculomegaly is frequently diagnosed antenatally and hence the perinatologist is faced with counselling the prospective parents. This review considers the diagnosis, management and prognosis of this condition. A particular emphasis is placed on the outcome of isolated ventriculomegaly as these are commonly the most difficult to counsel antenatally.